Molecular Identification of Dried Shellfish Products Sold on the Market Using DNA Barcoding

The dried shellfish products with rich nutrients and low-calorie content are favorite food in China,especially in coastal areas.However,the species of dried shellfish products in the market are usually unknown,as the taxonomic features were removed during the production process.This study described the application of DNA barcoding technique to the identification of 100 dried shellfish(scallop,squid,octopus and cuttlefish)products in markets.Samples were authenticated by comparing mitochondrial cytochrome oxidase subunit I(COI)gene and 16S ribosomal RNA(16S rRNA)gene sequences with public reference taxonomic databases.The results showed that all the 100 products can be identified at species level.Sixty four scallop adductor products were processed using the bay scallop,Argopecten irradians,and one was from Portuguese oyster,Crassostrea angulata.All the 27 squid,2 cuttlefish and 6 octopus products were produced by the Jumbo flying squid,Dosidicus gigas.The neighbour-joining tree is in agreement with the results of DNA barcoding analysis.The 64 scallop samples formed one A.irradians cluster,leaving Sca65 clustered with the reference oyster sequence C.angulata(MH997922).All the 35 cephalopod(squid,octopus and cuttlefish)samples formed a D.gigas cluster.This investigation revealed a low variety of dried shellfish products sold on the market,and highlighted the high rate of mislabeling and species substitution.Our present work provides a practical method for tracing and authenticating shellfish products.

Comparison of Anti-inflammatory and Analgesic Effects of Fresh and Dry Products of Zhuang Medicine Asystaia gangetica

[Objectives]To compare anti-inflammatory and analgesic effects of fresh and dry products of Zhuang medicine Asystaia gangetica on mice.[Methods]Experiments were performed using glacial acetic acid to increase capillary permeability in mice,cotton ball to cause granulomatous formation in mice,xylene to cause auricular swelling in mice,chronic inflammation,and acetic acid-induced pain and hot-plate pain.Besides,the anti-inflammatory and analgesic effects of fresh and dry products of A.gangetica on mice were observed with the indicators of capillary permeability in the abdominal cavity,swelling rate of auricles,cotton ball granulomas and writhing times,and thermal pain threshold.[Results]Fresh products of A.gangetica had significant inhibitory effects on peritoneal capillary permeability increase in mice induced by glacial acetic acid,mouse auricle swelling induced by xylene,and mouse granuloma formation induced by cotton balls.Dry products of A.gangetica also significantly inhibited the auricle swelling in mice induced by xylene,but the effect intensity was weaker than that of fresh products.In addition,dry products of A.gangetica showed a certain tendency to inhibit the increase of capillary permeability in the abdominal cavity of mice induced by glacial acetic acid.In the analgesic experiment,both fresh and dry products of A.gangetica showed better analgesic effect,but caused pain on the hot plate,and the analgesic effect time of fresh products was shorter than that of dry products.[Conclusions]Both fresh and dry products of Zhuang medicine A.gangetica have certain anti-inflammatory and analgesic effects.

Analysis on Dry Matter Production Characteristics of Super Hybrid Rice

Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha, were used as materials to study the dry matter production characteristics. The super hybrid rice showed a high ability in dry matter production and accumulation and its yield enhanced with the increase of dry matter accumulation. The advantage period of dry matter production in the super hybrid rice was mainly at the middle and late growth stages compared with the check. The grain yield had no significant correlation with the dry matter accumulation before the elongation stage while had a significantly positive correlation with the dry matter accumulation from the elongation to maturity stages in super hybrid rice. There were more dry matter in vegetative organs at the heading stage in the super hybrid rice but its contribution to yield （apparent conversion percentage） was averagely 4.3 percent points lower than that in the check. For crop growth rate （CGR）, the comparative advantage of super hybrid rice was at the middle and late stages, especially after flowering. Moreover, as the rising of leaf area index （LAI） and leaf area duration （LAD）, CGR enhanced. The total LAD and the mean of lAD per day of super hybrid rice was about 14.79% and 10.31% higher than those of the check, respectively. The results indicate that the high yield of super hybrid rice mostly comes from the products of photosynthesis after heading, which is shown by the increased CGR at middle and later stages. It is suggested that LAD character might be used to better explain the advantage in the dry matter production of super hybrid rice than LAI.

Effects of clipping on dry matter production and nutrients in the fernland of Hong Kong

The dry matter production and its nutrient amounts varied significantly with time and period from April to June was a favourable season for plant growth. Dry matter production declined significantly with clipping. Especially, repeated cutting of high frequencies for the long term had a severe effect on dry matter production. However, N, P, and K amounts in dry matter production did not significantly decline because the concentrations of N, P, and K in the plants increased with clipping. Repeated cutting for long term is a reason why net primary production has been depressed in the most of upland areas of southern China.

Growth characteristics and grain yield of machine-transplanted medium indica hybrid rice with high daily yield

High-yield rice varieties with a suitable growth duration are required for mechanical transplanting in multiple cropping systems. Daily yield is an appropriate criterion for the selection of machine-transplanted rice varieties. The aim of this study was to investigate the growth characteristics and grain production in machine-transplanted medium indica hybrid rice with a high daily yield. We conducted a field experiment on 20 medium indica hybrid rice varieties in 2017 and 2018.Grain yield decreased significantly with growth duration between jointing and heading, but it increased with dry matter accumulation, growth rate between jointing and heading, dry matter partitioning to the stem plus sheath at heading, daily yield, and number of spikelets per panicle. Compared with the medium and low daily yield variety types, the high daily yield variety type increased shoot biomass by improving crop growth rate and dry matter accumulation amount between jointing and heading and after heading. The high daily yield variety type decreased the growth duration pre-heading and the proportions of dry matter partitioned to the leaf lamina at heading and maturity, but it also increased the post-heading accumulated dry matter in the grain and the remobilization of dry matter stored in the vegetative organs. Furthermore,the high daily yield variety type significantly increased the occurrence rate of tillers, which is beneficial for the formation of a larger panicle size and an increase in the grain-filling rate. These changes contributed to a 6.51–23.16% relative increase in grain yield of the high daily yield variety type. In conclusion, the selection of high daily yield indica hybrid rice varieties with shorter pre-heading growth duration, greater tiller occurrence rate and spikelet numbers per panicle, higher post-jointing growth rates and stem plus sheath dry matter accumulation at heading is suitable for machine-transplanted rice.

Establishment of ANEDr model for evaluating absorbed-nitrogen effects on wheat dry matter production

Applying mathematic models to evaluate absorbed-N effects on dry matter production at different developmental stages would help determine proper nitrogen management according to crop demands and yield target. Two field trials were carried out for establishing absorbed-N effects on dry matter production（ANEDr） model, using uniform design in 2010–2011and 2012–2013 winter wheat growing seasons in Hebei Province, China. Another field trial was carried out in 2010–2011for model validation. Dry matter and N concentration in leaf and non-leaf organs were measured at setting, jointing, anthesis, and maturity. Theory of best linear unbiased prediction（BLUP） was applied to analyse the N effects of leaf and non-leaf organs on dry matter production. Within ANEDr model, four N-affected phases at each stage were concerned,leaf absorbed-N effect before this stage, non-leaf organ absorbed-N effect before this stage,leaf absorbed-N effect at this stage, and non-leaf organ absorbed-N effect at this stage. In addition, developmental processes, genotype characters and temperature were three factors that determine each N effect. It was demonstrated that ANEDr model can precisely quantify absorbed-N effects on dry matter production with high correlation coefficient（r=0.95）. Comparing with other models, ANEDr model considered both leaf and non-leaf organs according to developmental processes of winter wheat, showed higher flexibility and simplicity, thus could be applied to different environments, cultivars and crops after parameter adjustment.

The heterotic effects on dry matter production and grain yield formation in hybrid rice

We studied the characteristics of dry matterproduction and matter partitioning in hybridrice and the relationships of them with heterot-ic effect in 1993. Two popular indica hybrids, Shanyou 63(Zhenshan 97A/Minhui 63 ) and Teyou 63(Longtepu A/Minhui 63), as well as theircommon restorer line, Minhui 63 (elite cultivar

Physiological Responses of Zea mays Seedlings to Interactions Between Cadmium and Salinity

The effects of 0, 2.5, 5.0, and 10.0 pmol/L Cd^2＋（Cd（NO3）2.4H2O） and 0, 10, 25, 50, and 100 mmol/L NaCl on growth, photosynthesis and the content of some ions in maize （Zea mays L.） were investigated in the present study. With Increasing concentrations of Cd^2＋ or NaCI alone in Hoagland nutrient solution, the chlorophylls and starch content decreased. Combination treatment with salinity and cadmium increased the negative effects observed following the two stresses alone. Plants exhibiting growth retardation in response to one mild stress factor （25-50 mmol/L NaCl） became more tolerant to the other stress factor （Cd）. The exposure of plants to cadmium caused a partial reversal of the effects of salinity. Root and shoot growth, ion accumulation and levels of photosynthetic pigments were improved at moderate concentrations of the two stress factors Imposed jointly.